The present invention relates to new mono-azide substituted naphthylene or rylene imide derivatives and their use as reagents in Click-reactions.
Perylene imides in general are known for their extraordinary thermal, chemical and photo-physical stability. They are widely used as pigments and dyestuffs, as photosensitizers in solar cells, in photovoltaic cells and in pigment lasers. Furthermore, they can be used as marker groups in processes for the detection of analytes, in particular in diagnostic or analytical processes for biological samples.
Their fluorescence excitation wavelengths above 500 nm are advantageous insofar as there are basically no signals deteriorating the measurement in this wavelength range arising from auto fluorescence of cells, biological tissues or biological fluids.
Click chemistry is a chemical philosophy introduced by Sharpless in 2001 and generally describes chemistry which is tailored to generate target substances quickly and reliably by joining small units together.
The well known [3+2]-cycloaddition of azides with terminal alkynes using a Cu-catalyst at ambient temperatures discovered concurrently and independently by the groups of Sharpless and Meldal is one of the best know examples of click-chemistry and is often referred to as the Click-reaction.
The difference between “click chemistry” and “click-reaction” is that the former is a chemical synthesis philosophy whereas the latter is a specific reaction and only one example of click-chemistry.
WO 2003/101972 describes reactions of terminal acetylenes and azides using Cu(I) as such or Cu(I) formed in situ by reduction of Cu(II) as a catalyst.
WO 2006/117,161 describes new labelling strategies for the sensitive detection of analytes in complex biological samples. One embodiment described therein is a method for detecting an analyte in a sample wherein
a sample is provided,
said sample is contacted with a functionalized compound comprising at least one functional group which is a first reaction partner for a click reaction under conditions wherein said compound forms an association product with the analyte to be detected,
the association product is contacted with a second reaction partner for a Click reaction under conditions where a Click reaction between the first and second reaction partner occurs, wherein the second reaction partner further comprises a marker group
and, finally,
said marker groups are detected. The Click reaction between an azide and an alkyne is mentioned as a preferred embodiment. Suitable marker groups mentioned are, e.g., fluorescent marker groups, hydrazones or oximes.
WO 2008/052775 relates to Click chemistry for the production of reporter molecules suitable for the detection of analytes, e.g. nucleic acids. According to this invention, reporter molecules comprising at least two different functional groups are provided which are selectively coupled to first and second reaction partners. Thus, a sequence specific detection of nucleic acids with high sensitivity is possible.
Neither perylene imides nor their derivatives are disclosed as reactants for the Click reaction.
In Tetrahedron 64, 1467-73 (2008) perylene diimide-oligonucleotide conjugates are disclosed, which are obtained by Huisgen [3+2]cycloaddition in water/DMSO using Cu(I) as catalyst. The perylene diimides used carry two azide groups attached to the imide nitrogen via a spacer. Due to the double substitution with azide groups at both nitrogen atoms of the imide groups, crosslinking and chain elongation reactions might occur, which makes the use of the bis-azides as marker reagent not preferable.
WO 2007/054470 discloses rylene derivatives and their use as photosensibilizer in solar cells. Perylene diimides are included in the compounds disclosed.